scsi: hisi_sas: Change common allocation mode of device id

To reduce possibility of hitting unknown SoC bugs and aid debugging and
test, change allocation mode of device id from last used device id instead
of lowest available index.

Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/hisi_sas/hisi_sas.h b/drivers/scsi/hisi_sas/hisi_sas.h
index 3c8840089cd50e0fe10cf4d94944c0a9fbae953a..b4717bd8af3f06b6b578a1ae38641af41bd70d44 100644 (file)
--- a/drivers/scsi/hisi_sas/hisi_sas.h
+++ b/drivers/scsi/hisi_sas/hisi_sas.h
@@ -275,6 +275,7 @@ struct hisi_hba {
 
        int slot_index_count;
        int last_slot_index;
+       int last_dev_id;
        unsigned long *slot_index_tags;
        unsigned long reject_stp_links_msk;
 

diff --git a/drivers/scsi/hisi_sas/hisi_sas_main.c b/drivers/scsi/hisi_sas/hisi_sas_main.c
index 796fdfc73c758f299c228148ecdf941c86cc607e..a7e4c6e77068f0faa5dda2c8401a1e42522622d6 100644 (file)
--- a/drivers/scsi/hisi_sas/hisi_sas_main.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_main.c
@@ -596,10 +596,12 @@ static struct hisi_sas_device *hisi_sas_alloc_dev(struct domain_device *device)
        struct hisi_hba *hisi_hba = dev_to_hisi_hba(device);
        struct hisi_sas_device *sas_dev = NULL;
        unsigned long flags;
+       int last = hisi_hba->last_dev_id;
+       int first = (hisi_hba->last_dev_id + 1) % HISI_SAS_MAX_DEVICES;
        int i;
 
        spin_lock_irqsave(&hisi_hba->lock, flags);
-       for (i = 0; i < HISI_SAS_MAX_DEVICES; i++) {
+       for (i = first; i != last; i %= HISI_SAS_MAX_DEVICES) {
                if (hisi_hba->devices[i].dev_type == SAS_PHY_UNUSED) {
                        int queue = i % hisi_hba->queue_count;
                        struct hisi_sas_dq *dq = &hisi_hba->dq[queue];
@@ -614,7 +616,9 @@ static struct hisi_sas_device *hisi_sas_alloc_dev(struct domain_device *device)
                        INIT_LIST_HEAD(&hisi_hba->devices[i].list);
                        break;
                }
+               i++;
        }
+       hisi_hba->last_dev_id = i;
        spin_unlock_irqrestore(&hisi_hba->lock, flags);
 
        return sas_dev;